Re: your July 7 Quick Hits query re "Balloon Busters": During WWI both sides used moored balloons and blimps to direct artillery strikes. An observor in a basket would telegraph enemy positions down by wire. Obviously both sides wanted to shoot the other side's balloons down, so there were fighter pilots who specialized in low level high speed attacks. And since both sides knew the other side would try to shoot down their balloons, they'd protect the balloons with defensive aircraft and anti-aircraft guns on the ground.